The Effects of Non-Equilibrium States and Storage Conditions on Glass Transitions in Food

Food products with low water activity, dried, or frozen, are usually stored at non-equilibrium states, in which long-term stability cannot be assured. Changes in the storage conditions, including temperature and relative humidity, as well as internal diffusion of water and other compounds may affect the glass transition of foods, leading to deleterious effects on the product quality. The objective of this chapter is reviewing the main storage conditions that influence the glass transition of food materials, focusing on low-moisture and frozen products, in addition to discussing different approaches to applying in search of enhancing product stability and increasing shelf-life of foods.